Comminuting mill



Oct. 1, 1940. c. R DlMM ET AL 2,216,612

COMMINUTING MILL I Filed May 28, 1959 2 Sheets-Sheet 1 I ull I HIII I2.

INVENTORS Oct. 1 1940. Q R, DlMM ET AL 9 2,216,612

COMMINUTING MILL Filed May 28, 1938 2 Sheets-Sheet 2 Patented Oct. 1, 1940 UNITED STATES PATENT OFFICE COMLIINUTING MILL sylvania Application May 28, 1938, Serial No. 210,760

3 Claims.

This invention relates to improvements in comminuting mills, being concerned in particular with a mill of the kind wherein the reducin operations are performed by co-operating rotat ing and stationary knives which are adjustable in accordance with the characteristics of the particular material and the desired degree of reduction.

One object of the invention is to provide a mill which is available for use in connection with materials having widely different properties and which is characterized by features which adapt A still further object is to provide a novel design and arrangement of the parts of the mill,

whereby the various parts may be assembled and taken apart with facility and are capable of easily withstanding the severe strains which are attendant with the use of the mill.

The invention is illustrated in the accompanying drawings in which:

Figure 1 is a perspective View of a mill embodying the features of the invention.

Figure 2 is an enlarged transverse section taken along line 2--2 of Figure 1.

Figure 3 is a longitudinal section taken along line 3-3 of Figure 2, a portion of the rotating head and one bearing housing being shown in elevation.

The casing of the mill is indicated at 6. As illustrated, it includes end castings I and 8 which are connected at their bases by angle bars 9 and which carry bearing housings l0 for a shaft ll.

The said shaft extends through a working chamber l2 into which the material to be reduced is introduced through a hopper I20. and carries a head l3, the latter being located in the working chamber and being secured to the shaft by a key M and threaded element IS. A balance wheel I6 is mounted upon the shaft H and is available for connecting the said shaft to a suitable motor. The bottom of the working chamber I2 is provided by a semi-cylindrical screen H, the mesh of the latter being predetermined in 'accordance with the desired grade to which the material is to be reduced. The said screen is located over an outlet chamber I8 and is removably secured to ribs I9 and 20 by clamps 2|, the said ribs being welded or otherwise secured at their opposite ends to the castings I and 8. The clamps 2| are carried by bolts 22 which are supported by the said ribs and co-operate with 5 'lips 23 formed or provided along the upper marginal edges of the screen. Access to the outlet chamber l8 may be had through openings 24 which are located at opposite sides of the casing and which are normally closed by doors 25.

The head I3 is formed or provided with arms 26 which terminate in flanges 21. The latter extend substantially at right angles with respect to the body portions of the arms; they are arranged lengthwise of the working chamber and carry knives 28. The said knives are secured to the flanges 21 on the sides facing the directionjof rotation of the head (see arrow in Figure 2) by bolts-29 which pass through slots 30 formed in the knives and enter threaded holes in the flanges. The slots 30 extend transversely of the knives and provide for their adjustment toward and away from the co-operating stationary knives, such adjustments as are made being maintained by bolts 3| which are carried by the arms 26 and which engage the rearmost edges of the knives, the said bolts preferably carrying lock nuts 32.

The bearing housings to, as illustrated, are removably secured in openings Illa which are formed in the end castings i and 8 and carry suitable anti-friction bearings lflb. Preferably the openings Illa are large enough to permit the head l3 to be passed through either of them into and out of the working chamber. Facility in assembling, dismantling and overhauling the mill is thus insured.

The knives 28 co-oerate with stationary knives 33 and 33a. The knives 33 are carried by ribs 34 which are arranged in an accurate series between the hopper l2a. and the rib 20 and which are welded or otherwise secured at their opposite ends to the castings 1 and 8 while the knife 33a is carried by the rib l9 and is, therefore, located at the opposite side of the said hopper. 5 The said ribs are preferably machined to provide inclined faces 35 against which the knives 33 and 33a are secured by bolts 36. The latter pass through slots 38 (Figures 2 and 3) which are formed transversely of the knives and enter threaded openings in the ribs. The slots 38 provide for adjustment of the knives 33 and 33a toward and away from the knives carried by the head I3, bolts 39 which are carried by shoulders 31 of the ribs being available in connection with lock nuts 43 to maintain the knives in the pomwhich is formed to provide a working chamber,

tion to which they are adjusted. a rotary head in said chamber, a knife carried The ribs 34 define windows 4! which extend by said head, a window in said housing, a rib lengthwise of the housing and which are normally which extends substantially parallel with the axis closed by covers 42. One of the marginal edges of said head and which provides one wall of said of each of the said covers fits against a shoulder window, a second knife carried by said which -31 of one of the ribs while the opposite edge fits co-operates with said first named knife, means against the upper edge of the adjacent rib. The for adjusting one of said knives with respect to covers are formed with inwardly directed webs the other to vary the clearance between their 43 which carry flanges 44. The said flanges are cutting edges, said window providing for the inspaced from the faces 35 of the ribs to prdvide spection of said clearance and a removable cover openings through which the knives 33 extend. w h normally closes said window, said cover Their opposite edges, however, fit against the having an' inwardly extending web which carries lower edges of the adjacent ribs. The covers also a flange, one side of saidflange engaging one wall carry end extensions 45 which overlie the end of said window and the other side extending adcastings I and 8 and which are formed with open jacent the cutting edge of said second knife, the ended slots 45, the latter being adapted to accom-' inner surfaces of said rib and flange being arcumodate bolts 41 which are pivotally mounted upon ate and having a common radius, the center of pins 48. The said bolts carry wing nuts 49 which which is located substantially at said axis. may be tightened down upon the extensions 45 to 2. A comminuting mill including a housing secure the covers in their respective windows. which is formed to provide a working chamber, The knife 33a extends into the working chama rotary head in said chamber, a knife carried her below a door 52 which fits in an opening 53 by said head, a window in said housing having and which is held in its closed position by screws stationary side walls which are substantially par- 54. The said door serves the same pupose as allel with the axis of said head, one of said walls the removable covers 42, being removable to enbeing formed with a longitudinally extending able inspection and gauging of the clearance beshoulder, a second knife, a threaded element for tween the cutting edge of the knife 33a and the securing said second knife to said last named wall cutting edges of the knives 28. under said shoulder in co-operating relation with It will be apparent that the mounting of the respect to said first mentioned knife, one of said knives 28, 33 and 33a in the manner described knives being adjustable with respect to the other provides for their convenient adjustment to vary to vary the clearance between their cutting edges, the clearances between their cutting edges. Such said window providing for the inspection of said adjustments, including thosetoprovide minimum clearance and a cover which is removably seclearances, may be made accurately and with cured in said window, said cover having outer facility as the removable covers 42 and the door and inner flanges joined by an integral connect- 52 provide for the inspection and accurate gauging web which is spaced from said threaded eleing of the clearances between the co-operating ment, said outer flange having longitudinal edges lmives throughout their entire length, It will be which engage said shoulder and the other of said noted that the stationary and movable knives are walls and said inner flange having one edge so mounted that such forces as are transmitted which engages said last named wall and another to them during operation of the mill are only inedge which extends adjacent the cutting edge directly applied to the bolts by which they are of said second knife. secured to the head and'casing. The greater por- 3. A comminuting mill including a housing tion of such forces are taken up directly by the which is formed to provide a working chamber, flanges 21 in the case of the movable knives and a rotary head in said chamber, a knife carried by the ribs l9 and 34 in the case of the stationary said head, a window in said housing, a. rib which knives. The subjection of the bolts 29 and 35 extends substantially parallel with the axis of to excessive strains is thus avoided. In this consaid head and which provides one wall of said nection, it will also be noted that the covers 42 window, said wall being formed with a longitudinot only close the windows 4| but they also serve nally extending shoulder, a second knife, means to reinforce the ribs 34. As each cover abuts the for adjustably securing said second knife to said upper and lower edges of the back of one rib and last named wall under said shoulder, whereby the shoulder 31 of an adjacent rib, the covers the clearance between the cutting edges of said and ribs provide a continuous arcuate wall which knives may be varied, said window providing for is capable of easily withstanding the forces t the inspection of said clearance and a cover which it is subjected during operation of the mill w c is removably Secured in Said W w, d without yielding of the ribs to permit movement Cover having O e and inner flanges J' e by of the stationary knives. The construction dean integral Connecting Said Outer flange scribed, therefore, not only enables minimum having longitudinal edges which engage said clearances to be provided between the stationary and rotary knives but also insures the maintenance of such clearances under operating conditions. The mill thus has the advantage that it adjacent the cutting edge of said second knife, maybe employed in connection with the reducthe inner surfaces of said rib and inner flange tion of various materials such as, for example, being arcuate and having a common --radius, the scrap rubber tires, leather, rags, felt, roots, bark, center of which is located substantially at said plastic materials and various chemicals and axis. chemical compounds. i

We claim as our invention: 1. A comminuting mill including a housing inner flange having one edge which engages said last named wall and another edge which extends CHANDOS ROY DIMM. annnanno GERMAN AVILA.

shoulder and the other of said walls and said 

